KOPP GLASS red fresnel warning beacon light lens (and an old porcelain ceiling fixture)

New member Lani showed her similar little red lens the other day (wondering if it was an insulator) which got me thinking...I don't have one quite that small (wish I did, it's *cute*!) but I DO have several others kinda like it...? ;-) Here's the biggest one of 'em. :-)

From ebay several years ago, it measures about 7-1/2" tall by 4" across, made of sturdy (molded) red glass with threads on the outside of its open end such that it would have 'screwed on' to its original fixture. I don't have one of whatever those exact fixtures were, instead displaying it sitting in a wonderful vintage (1940's?) white porcelain ceiling light fixture I mounted to a painted plywood circle/base. Sorta funny story there, I actually also bought what I thought *was* one of the correct fixtures for a lens like this (from another seller) at the same time -- but when whichever was the 2nd box arrived, I immediately realized that I'd made a big error in judgement (and/or either seller wasn't completely clear with dimensions of things, or whatever) since the two were more than an inch off... <groan><headdesk> but happily, it accidentally ended up being perfectly sized for the old porcelain fixture (from the ReStore I think, it first found encrusted in numerous thick layers of ceiling paint but turning out to be a lovely thing unto itself once I cleaned all that crap off of it) that I already had.

On either side of its edge (on the open end) it is identified with manufacturer's part# lettering "KOPP AP 3519 MADE IN U.S.A." and "['K in a circle' KOPP logo] AN2541-".